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The CCDC CIF Deposition Guidelines

When preparing your CIF for deposition please include as much information as possible and check it carefully. This is especially true for CSD Communications where there is no paper to describe the chemistry and experimental details leading to your structure. If you choose to publish your data as a CSD Communication please remember to provide all the authors/crystallographers/chemists who contributed to the crystallographic experiment as authors of the data. If we are unable to validate your structure from the information you have provided we may contact you. If we cannot resolve the issue, unfortunately, we may not be able to add your structure to the CSD.

All experimental CIF files (including those from powder diffraction experiments) should contain an R-factor. This should be consistent with the crystallography being performed correctly and to the best ability that would be expected from the material and equipment used. We would like all experimental CIFs to contain:

R-factors (R1, wR2, Rint)

GooF

Shift/ESD (to show that the refinement has converged)

Explanation of any problems with numbers of reflections and parameters

Any residual electron density

Details of squeeze/solvent masking

Atomic Displacement Parameter (ADP) values

Temperature – cell and data collection temperatures match

Experimental set up including mounting device and instrument type

HKL included

RES included

We would encourage you to take advantage of the IUCr checkCIF reports built in to the deposition page. This can highlight issues to check with your structure that can be clarified in the validation reply form, particularly in the case of A- or B- level alerts. Ideally, treatment of disorder or partial occupancy atoms should be clear and of course, no non-positive definite atoms!

To allow us to create the most accurate representation of your structure please provide as much additional information on the “Enhanced Data” page as is appropriate for your structure. Some chemical issues we commonly encounter when processing data into the CSD are:

Given formula and crystal formula don’t agree. Particular attention should be paid to hydrogen atoms which may not be located in the experiment. It would be very helpful to us to have a complete moiety formula (including unlocated hydrogens and any SQUEEZE/MASK species not located, if known)

Charge balance, particularly for variable metal oxidation states and radicals

Missing hydrogen atoms, especially on oxygen atoms that could be hydroxy/oxy/aqua ligands and for polyoxometalate structures

Unusual bonding, tautomers or metal-metal bonding

Poorly handled or unmodelled disorder

Unexplained void space not accounted for by SQUEEZE or MASK procedures

Further information that will benefit the users of your structure and that will enable the correct identification of any previous versions of your structure are:

Stereochemical determination method, if relevant

Crystallisation solvent/conditions

Melting point

Details of re-refinement – please tell us if the structure is a re-refined version of an existing CSD entry.